Overview
Gout, also called gouty arthritis, is a disease of how the body processes nutrients (metabolism) in which crystals of uric acid are deposited in the joints, tendons, and skin. Most commonly affecting men, gout emerges as the sudden development of swollen, red, hot, tender joints, especially at the big (great) toe, ankle, wrist, and knee.
Uric acid is a substance resulting from the breakdown (metabolism) of purines, which are proteins found in human tissues and in many foods. Gout is caused by elevated levels of uric acid in the blood, due to either increased production of uric acid or decreased excretion of uric acid by the kidney. The excess uric acid is deposited as needle-like crystals in the cartilage and tissue surrounding joints, in the skin, and in the kidneys. These deposits cause inflammation, which can ultimately result in joint destruction, nodules called tophi, or kidney stones.
Gout is often diagnosed clinically, though several tests, including blood work and X-rays, are usually performed to confirm the diagnosis. The definitive diagnosis of gout is based on microscopic examination of fluid from an affected joint.
